Accumulated Other Comprehensive Income- Schedule of Balances of Each Component (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
Accumulated Other Comprehensive Income
Balance at the beginning of the period	$ 206,664	$ 244,012	$ 239,670	$ 244,796
Other comprehensive income (loss) before reclassifications	1,183	126	1,676	322
Reclassification to (earnings) loss	(49)	(83)	(151)	(247)
Net current-period other comprehensive income (loss)	1,134	43	1,525	75
Balance at the end of the period	212,000	236,459	212,000	236,459
Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income
Balance at the beginning of the period	2,371	2,169	1,980	2,137
Balance at the end of the period	3,505	2,212	3,505	2,212
Unrealized Investment Gain (Loss)
Accumulated Other Comprehensive Income
Balance at the beginning of the period	0	4	0	32
Other comprehensive income (loss) before reclassifications	0	(3)	0	(31)
Reclassification to (earnings) loss	0	0	0	0
Net current-period other comprehensive income (loss)	0	(3)	0	(31)
Balance at the end of the period	0	1	0	1
Postemployment Benefits Net Actuarial Gain (Loss)
Accumulated Other Comprehensive Income
Balance at the beginning of the period	2,197	2,165	1,980	2,105
Other comprehensive income (loss) before reclassifications	185	129	603	353
Reclassification to (earnings) loss	(95)	(83)	(296)	(247)
Net current-period other comprehensive income (loss)	90	46	307	106
Balance at the end of the period	2,287	2,211	2,287	2,211
Interest Rate Swap Gain (Loss)
Accumulated Other Comprehensive Income
Balance at the beginning of the period	174	0	0	0
Other comprehensive income (loss) before reclassifications	998	0	1,073	0
Reclassification to (earnings) loss	46	0	145	0
Net current-period other comprehensive income (loss)	1,044	0	1,218	0
Balance at the end of the period	$ 1,218	$ 0	$ 1,218	$ 0